from __future__ import print_function

try:
    xrange  # Python 2
except NameError:
    xrange = range  # Python 3

try:
    raw_input  # Python 2
except NameError:
    raw_input = input  # Python 3

'''
The number of partitions of a number n into at least k parts equals the number of partitions into exactly k parts
plus the number of partitions into at least k-1 parts. Subtracting 1 from each part of a partition of n into k parts
gives a partition of n-k into k parts. These two facts together are used for this algorithm.
'''


def partition(m):
    memo = [[0 for _ in xrange(m)] for _ in xrange(m + 1)]
    for i in xrange(m + 1):
        memo[i][0] = 1

    for n in xrange(m + 1):
        for k in xrange(1, m):
            memo[n][k] += memo[n][k - 1]
            if n - k > 0:
                memo[n][k] += memo[n - k - 1][k]

    return memo[m][m - 1]


if __name__ == '__main__':
    import sys

    if len(sys.argv) == 1:
        try:
            n = int(raw_input('Enter a number: '))
            print(partition(n))
        except ValueError:
            print('Please enter a number.')
    else:
        try:
            n = int(sys.argv[1])
            print(partition(n))
        except ValueError:
            print('Please pass a number.')
